Stove-pipe damper



(No Model.)

J. H DOHERTY.

STOVE PIPE DAMPER.

Patented Aug. 4, 1885.

FIG .1.

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JOHN H. DOHERTY, OF SAN FRANCISCO, CALIFORNIA.

STOVE-PIPE DAMPER.

EBPBCIFIGATION' forming part of Letters Patent No. 323,568, dated August4, 1885.

Application filed December 17, 1884. (No model.)

To otZZ whom it may concern.-

Be it known that 1, JOHN E. DOHERTY, a citizen of the United States,residing in the city and county of San Francisco, State of California,have invented a new and useful Improvement in StovePipe Dampers, ofwhich the following is a specification.

The object of my invention is to provide a means whereby the spaces orperforations of a damper plate will be opened and closed automatically,and at the same time to combine with. an automatic stove-pipe damper anordinary dampenplate to be operated independently of the automaticplate, and in the usual way. I accomplish this object by the meansillustrated in the accompanying drawings,in which Figure 1 is a top viewof my improved stove-pipe damper. Fig. 2 is a bottom view showing thehinged flap partly broken away. Fig. 3 is a vertical section through thestovepipe, showing the damper in side elevation.

Similar letters of reference are used to in dicate like parts throughoutthe several fig ures.

A represents a pivoted base-plate provided with radial openings, and Bisa plate formed with radial arms to fit over the openings in the plate A.The plate Bis pivoted to the plate A. centrally, so that it will move onits pivot and open or close the radial openings in the plate A in thesame manner as that of a hot-air or other register.

Surrounding the plate B is a metallic ring, 0, which is connected to theplate A at one point-namely, at D-and this ring extends partially aroundthe plate, as shown. The ring (3 is composed of some metal capable ofrapid expansion and contraction by changes in temperature, and copper,brass, zinc, or other metal may be employed. Copper, however, ispreferable.

To the free end of the ring E is connected an arm, E, which in turnconnects with a lever arm, F, which latter is curved at its outer end,and maybe provided with take-up holes.

From the lever-arm F extends backward or downward, according to thehorizontal or vertical position of the damper, as the case maybe, anarm, G, with its lower end split to receive a projecting pin, H, placedeccentrio to the pivotal pin which holds the two plates together. Thissystem of levers is pivoted to the plate 13 at I I, as shown.

In operation, when the free end E of the expansible ring is connected tothe lever E, and expansion or contraction of the ring takes place, itwill raise up or depress the levers connected with the register-plate B,and expose or cover up the openings in the plate A, in accordance withthe degrees of heat which operate upon the metal of the expansible ring.

In order to combine the ordinary damper with my automatic damper, Iemploy a disk or flap, J, with its upper edge or side re moved, and thisis hinged to the back and under side of the plate A, so that when thedamper is in a horizontal position in the stove pipe this plate J willfall down by its gravity and hang in that position until the position ofthe whole damper is changed to a vertical or edgewise position, when theplate will fall or swing down against the plate A, as shown in plan inFig. 2, and shut off the draft irrespective of the automatic plate orregister, leaving a passage,however,above the truncated portion for theescape of gases through the register-openings in the plate A.

It should here be observed that this hinged plate will also serve tokeep the damper free from soot that has accumulated thereon by impact orstriking against the damper-plate when assuming its iiatwise positionover the said damper-plate.

Having thus described my inveutiomwhat I claim, and desire to secure byLetters Patent, is-

In combination with a stove-pipe damper or ventilating device capable ofbeing opened and closed in an automatic manner by means of an eXpansiblcring surrounding the movable plate of such damper, and connected theretoby suitable arms and levers,the hinged flap or plate J,adapted to fallby gravity upon or against the plate A, at the rear portion or sidethereof, and act in the capacity of an ordinary stove-pipe damper,constructed and arranged to operate substantially in the manner asherein'set forth and specified.

In testimony that I claim the foregoing I have hereunto set my hand andseal.

lVitnesses: JOHN H. llOllEll'll. [a s] WILMER BRADFORD, (ll-ms. E.KELLY.

IOC

